Determination of ochratoxin A in meat products by higt-permormance liquid chromatography coupled to electrospray ionisation sequential mass spectrometry

A method based on liquid chromatography with electrospray ionisation ion trap mass spectrometry, for the determination of ochratoxin A (OTA) in meat products using ochratoxin B (OTB) as an internal standard, is described. Fragmentation patterns of OTA and OTB were studied by sequential mass spectrometry. Trace determination was then accomplished by consecutive reaction monitoring (CRM) of a fragment obtained by MS3 experiments. This led to a better signal-to-noise ratio and to a higher specificity of the technique. The response to OTA was linear over at least one concentration decade with a limit of detection of 0.6 ng/g. The method was applied to pig tissue samples naturally contaminated by OTA.